diff --git a/lua/Trans/conf.lua b/lua/Trans/conf.lua
index 48b2b35..37acd42 100644
--- a/lua/Trans/conf.lua
+++ b/lua/Trans/conf.lua
@@ -1,7 +1,7 @@
 return {
     display = {
         style = 'minimal',
-        max_height = 50,
+        max_height = 50, -- 小于0代表无限制
         max_width = 50,
         -- phnoetic = true,
         collins_star = true,
@@ -30,8 +30,7 @@ return {
         notOxford = ''
     },
     auto_close = true,
-    -- TODO: async process
-    -- async = false,
+    buf = vim.api.nvim_create_buf(false, true)
 
     -- TODO:  add online translate engine
     -- online_search = {
@@ -39,11 +38,5 @@ return {
     --     engine = {},
     -- }
 
-    -- TODO: precise match or return closest match result
-    -- precise_match = true,
-
-    -- TODO: lemma search
-    -- lemma = false,
-
     -- TODO: register word
 }
diff --git a/lua/Trans/display.lua b/lua/Trans/display.lua
index 968ef49..e2b26e7 100644
--- a/lua/Trans/display.lua
+++ b/lua/Trans/display.lua
@@ -1,29 +1,34 @@
 local M = {}
 
+local api     = vim.api
 local display = require("Trans").conf.display
-local icon = require("Trans").conf.icon
-local order = require("Trans").conf.order
+local icon    = require("Trans").conf.icon
+local order   = require("Trans").conf.order
 
+local hl = require("Trans.highlight").hlgroup
 
-local buf = vim.api.nvim_create_buf(false, true)
+local buf = require("Trans.conf").buf
 local win = 0
-vim.api.nvim_buf_set_option(buf, 'filetype', 'Trans')
+local line = 0
+local pos_info = {}
+
+api.nvim_buf_set_option(buf, 'filetype', 'Trans')
 
 
 local function show_win(width, height)
-    win = vim.api.nvim_open_win(buf, false, {
+    win = api.nvim_open_win(buf, false, {
         relative = 'cursor',
         title = 'Trans',
         title_pos = 'center',
         style = display.style,
         col = display.offset_x,
         row = display.offset_y,
-        width = width > display.max_width and display.max_width or width,
-        height = height > display.max_height and display.max_height or height,
+        width = (display.max_width > 0 and width > display.max_width) and display.max_width or width,
+        height = (display.max_width > 0 and height > display.max_height) and display.max_height or height,
         border = display.border_style,
         focusable = true,
     })
-    vim.api.nvim_win_set_option(win, 'wrap', display.wrap)
+    api.nvim_win_set_option(win, 'wrap', display.wrap)
 end
 
 -- NOTE: title
@@ -32,35 +37,54 @@ local function get_title(text, query_res)
         (display.oxford and (query_res.oxford == 1 and icon.isOxford .. '    ' or icon.notOxford .. '    ') or '') ..
         ((display.collins_star and query_res.collins) and string.rep(icon.star, query_res.collins) or '')
     table.insert(text, title)
+
+    pos_info.title = {}
+    pos_info.title.word = #query_res.word
+    pos_info.title.phonetic = #query_res.phonetic
+    pos_info.title.line = line
+    line = line + 1
 end
 
 -- NOTE: tag
 local function get_tag(text, query_res)
-    if #query_res.tag > 0 then
+    if query_res.tag and #query_res.tag > 0 then
         local tag = query_res.tag:gsub('zk', '中考'):gsub('gk', '高考'):gsub('ky', '考研'):gsub('cet4', '四级'):
             gsub('cet6', '六级'):
             gsub('ielts', '雅思'):gsub('toefl', '托福'):gsub('gre', 'GRE')
         table.insert(text, '标签:')
         table.insert(text, '    ' .. tag)
         table.insert(text, '')
+
+        pos_info.tag = line
+        line = line + 3
     end
 end
 
 -- NOTE: pos 词性
 local function get_pos(text, query_res)
-    if #query_res.pos > 0 then
+    if query_res.pos and #query_res.pos > 0 then
         table.insert(text, '词性:')
+
+        local content = 0
         for v in vim.gsplit(query_res.pos, [[/]]) do
             table.insert(text, string.format('    %s', v .. '%'))
+            content = content + 1
         end
+
         table.insert(text, '')
+
+        pos_info.pos = {}
+        pos_info.pos.line = line
+        pos_info.pos.content = content
+        line = line + content + 2
     end
 end
 
 -- NOTE: exchange
 local function get_exchange(text, query_res)
-    if #query_res.exchange > 0 then
+    if query_res.exchange and #query_res.exchange > 0 then
         table.insert(text, '词形变化:')
+
         local exchange_map = {
             p = '过去式',
             d = '过去分词',
@@ -71,38 +95,60 @@ local function get_exchange(text, query_res)
             O = '词干',
             ['3'] = '第三人称单数',
         }
+
+        local content = 0
         for v in vim.gsplit(query_res.exchange, [[/]]) do
             table.insert(text, string.format('    %s:  %s', exchange_map[v:sub(1, 1)], v:sub(3)))
+            content = content + 1
             -- FIXME: 中文字符与字母位宽不一致, 暂时无法对齐
         end
         table.insert(text, '')
+
+        pos_info.exchange = {}
+        pos_info.exchange.line = line
+        pos_info.exchange.content = content
+        line = line + content + 2
     end
 end
 
 -- NOTE: 中文翻译
 local function get_zh(text, query_res)
-    if #query_res.translation > 0 then
+    if query_res.translation then
         table.insert(text, '中文翻译:')
+
+        local content = 0
         for v in vim.gsplit(query_res.translation, '\n') do
             table.insert(text, '    ' .. v)
+            content = content + 1
         end
         table.insert(text, '')
+
+        pos_info.zh = {}
+        pos_info.zh.line = line
+        pos_info.zh.content = content
+        line = content + line + 2
     end
 end
 
-
 -- NOTE: 英文翻译
 local function get_en(text, query_res)
-    if #query_res.definition > 0 then
+    if query_res.definition and #query_res.definition > 0 then
         table.insert(text, '英文翻译:')
+
+        local content = 0
         for v in vim.gsplit(query_res.definition, '\n') do
             table.insert(text, '    ' .. v)
+            content = content + 1
         end
         table.insert(text, '')
+
+        pos_info.en = {}
+        pos_info.en.line = line
+        pos_info.en.content = content
+        line = line + content + 2
     end
 end
 
-
 local handler = {
     title = get_title,
     tag = get_tag,
@@ -122,28 +168,91 @@ local function get_text(query_res)
     return text
 end
 
-
-
 local function set_text(query_res)
     local text = query_res and get_text(query_res) or { '没有找到相关定义' }
 
-    vim.api.nvim_buf_set_lines(buf, 0, -1, false, text)
+    api.nvim_buf_set_lines(buf, 0, -1, false, text)
     local width = 0
     for _, v in ipairs(text) do
-        if v:len() > width then
+        if #v > width then
             width = v:len()
         end
     end
     return width, #text
 end
 
+local function hl_title()
+    api.nvim_buf_add_highlight(buf, -1, hl.word, pos_info.title.line, 0, pos_info.title.word)
+    api.nvim_buf_add_highlight(buf, -1, hl.phonetic, pos_info.title.line, pos_info.title.word + 5,
+        pos_info.title.word + 5 + pos_info.title.phonetic)
+end
+
+local function hl_tag()
+    if pos_info.tag then
+        api.nvim_buf_add_highlight(buf, -1, hl.ref, pos_info.tag, 0, -1)
+        api.nvim_buf_add_highlight(buf, -1, hl.tag, pos_info.tag + 1, 0, -1)
+    end
+end
+
+local function hl_pos()
+    if pos_info.pos then
+        api.nvim_buf_add_highlight(buf, -1, hl.ref, pos_info.pos.line, 0, -1)
+        for i = 1, pos_info.pos.content, 1 do
+            api.nvim_buf_add_highlight(buf, -1, hl.pos, pos_info.pos.line + i, 0, -1)
+        end
+    end
+end
+
+local function hl_exchange()
+    if pos_info.exchange then
+        api.nvim_buf_add_highlight(buf, -1, hl.ref, pos_info.exchange.line, 0, -1)
+        for i = 1, pos_info.exchange.content, 1 do
+            api.nvim_buf_add_highlight(buf, -1, hl.exchange, pos_info.exchange.line + i, 0, -1)
+        end
+    end
+end
+
+local function hl_zh()
+    api.nvim_buf_add_highlight(buf, -1, hl.ref, pos_info.zh.line, 0, -1)
+    for i = 1, pos_info.zh.content, 1 do
+        api.nvim_buf_add_highlight(buf, -1, hl.zh, pos_info.zh.line + i, 0, -1)
+    end
+end
+
+local function hl_en()
+    api.nvim_buf_add_highlight(buf, -1, hl.ref, pos_info.en.line, 0, -1)
+    for i = 1, pos_info.en.content, 1 do
+        api.nvim_buf_add_highlight(buf, -1, hl.en, pos_info.en.line + i, 0, -1)
+    end
+end
+
+local hl_handler = {
+    title = hl_title,
+    tag = hl_tag,
+    pos = hl_pos,
+    exchange = hl_exchange,
+    zh = hl_zh,
+    en = hl_en,
+}
+
+local function set_hl()
+    for _, v in ipairs(order) do
+        hl_handler[v]()
+    end
+end
+
+local function clear_tmp_info()
+    pos_info = {}
+    line = 0
+end
+
 function M.query_cursor()
-    vim.api.nvim_buf_set_option(buf, 'modifiable', true)
     local word = vim.fn.expand('<cword>')
     local res = require("Trans.database").query(word)
     local width, height = set_text(res)
     show_win(width, height)
-    vim.api.nvim_buf_set_option(buf, 'modifiable', false)
+    set_hl()
+    clear_tmp_info()
 end
 
 function M.query()
@@ -156,7 +265,7 @@ end
 
 function M.close_win()
     if win > 0 then
-        vim.api.nvim_win_close(win, true)
+        api.nvim_win_close(win, true)
         win = 0
     end
 end
diff --git a/lua/Trans/highlight.lua b/lua/Trans/highlight.lua
new file mode 100644
index 0000000..d509ab4
--- /dev/null
+++ b/lua/Trans/highlight.lua
@@ -0,0 +1,27 @@
+local M = {}
+
+M.hlgroup = {
+    word     = 'TransWord',
+    phonetic = 'TransPhonetic',
+    ref      = 'TransRef',
+    tag      = 'TransTag',
+    exchange = 'TransExchange',
+    pos      = 'TransPos',
+    zh       = 'TransZh',
+    en       = 'TransEn',
+}
+
+function M.set_hl()
+    -- FIXME: highlight doesn't work
+    local set_hl = vim.api.nvim_set_hl
+    set_hl(0, M.hlgroup.word, { fg = '#98c379', bold = true })
+    set_hl(0, M.hlgroup.phonetic, { fg = '#8b949e' })
+    set_hl(0, M.hlgroup.ref, { fg = '#75beff', bold = true })
+    set_hl(0, M.hlgroup.tag, { fg = '#e5c07b' })
+    set_hl(0, M.hlgroup.pos, { link = M.hlgroup.tag })
+    set_hl(0, M.hlgroup.exchange, { link = M.hlgroup.tag })
+    set_hl(0, M.hlgroup.zh, { fg = '#7ee787' })
+    set_hl(0, M.hlgroup.en, { fg = '#bc8cff' })
+end
+
+return M
diff --git a/lua/Trans/init.lua b/lua/Trans/init.lua
index 0338c4f..b1117e6 100644
--- a/lua/Trans/init.lua
+++ b/lua/Trans/init.lua
@@ -1,11 +1,5 @@
 local M = {}
 
--- NOTE:
--- Style:
---      [minimal]: one line with '/'
---      [default]:
---      [full]:    show all description in different lines
--- TODO: other style
 
 M.conf = require("Trans.conf")
 function M.setup(conf)
diff --git a/lua/Trans/setup.lua b/lua/Trans/setup.lua
index 2bfdabd..302ae5c 100644
--- a/lua/Trans/setup.lua
+++ b/lua/Trans/setup.lua
@@ -15,6 +15,7 @@ vim.api.nvim_create_autocmd('VimLeave', {
         end
     end,
 })
+
 -- TODO: set command to close preview window automatically
 local auto_close = require("Trans.conf").auto_close
 if auto_close then
@@ -25,3 +26,5 @@ if auto_close then
         callback = require('Trans.display').close_win
     })
 end
+
+require("Trans.highlight").set_hl()