faq English version (#915)

* Update README.md

* Create faq_EN.md

* Update faq.md
Co-authored-by: NPeter Pan <littlepanzh@gmail.com>
Co-authored-by: NYixinKristy <48054808+YixinKristy@users.noreply.github.com>

README.md

@@ -41,6 +41,7 @@ VisualDL natively supports the use of Python. Developers can retrieve plentiful
 * [Installation](#Installation)
 * [Usage Guideline](#Usage-Guideline)
 * [Function Preview](#Function-Preview)
+* [Frequently Asked Questions](#Frequently-Asked-Questions)
 * [Contribution](#Contribution)
 * [More Details](#More-Details)
 * [Technical Communication](#Technical-Communication)
@@ -359,6 +360,10 @@ Developers can compare multiple experiments by specifying and uploading the path
 </p>
 
 
+## Frequently Asked Questions
+
+If you are confronted with some problems when using VisualDL, please refer to [our FAQs](./docs/faq_EN.md).
+
 ## Contribution
 
 VisualDL, in which Graph is powered by [Netron](https://github.com/lutzroeder/netron), is an open source project supported by [PaddlePaddle](https://www.paddlepaddle.org/) and [ECharts](https://echarts.apache.org/).

docs/faq.md

 # 常见问题
 
+ [**English**](./faq_EN.md)
+
 ## 打开浏览器出现空白或者发生错误
 可参照下列步骤排除错误原因
 1. 确保启动VisualDL时指定的`logdir`路径正确，并确保其下有符合命名要求（文件名包含`vdlrecords`）的日志文件，可进入`logdir`指定的文件夹先行查看。若未解决，转下步。

docs/faq_EN.md

+# Frequently Asked Questions
+
+[**中文**](./faq.md)
+
+## How can I do when I see a blank page or error messages in the browser?
+To work out bugs, you can follow the steps： 
+1. You should ensure that the `logdir` path set by VisualDL is correct. In the meanwhile, there must be a log file and its name (including `vdlrecords`) should be correct. And then you can check the folder set by `logdir`. If it is not okay, try the next step.
+2. Please check the browser and its version, and ensure it fits VisualDL. We suggest using **the latest versions** of Chrome browser, browsers with Chrome’s kernel, Firefox browser. Please change browsers and upgrade it to the latest version. If it is not okay, try the next step.
+3. Please specify `--host`as `0.0.0.0` or `127.0.0.1`. And the latter one only supports the local address. If the server runs and you want to check by other addresses, please use `0.0.0.0` and ensure the end can be visited by outer net. If it is not okay, try the next step.
+4. Close and re-open the front-end page of VisualDL. Or do a hard refresh on the browser and wait for 15-30 seconds. If it is not okay, try the next step.
+5. If you use windows, please check whether the registry is modified. For users who want to get into more details, please refer to https://github.com/PaddlePaddle/VisualDL/issues/834. If all the steps do not work, please ask questions in VisualDL GitHub Issue. The link is [VDL Issue](https://github.com/PaddlePaddle/VisualDL/issues).
+
+## When I use modules of Image, Audio and Text, there are only ten samples.
+We apply random sampling algorithm to display sampled data, when using modules of Image, Audio and Text. In this way, the front-end page will not be stuck or will not crash because of too much data, and then we can ensure users’ experience. 
+
+Though data shown in the front-page are sampled, all the data are saved in the log file. You can obtain all the data by using `VisualDL.LogReader`. For more details, please refer to our [LogReader tutorial](./components#LogReader).
+
+## Why are the curves drawn by Scalar twisty?
+Because there are two or more values in a certain step, you will find the curves you draw are like the following picture. Please check your script and find whether you add several values to one step, when using`add_scalar`.
+
+<p align="center">
+    <img src="https://user-images.githubusercontent.com/28444161/99496785-de44d280-29af-11eb-8fbd-ebc7a4919f2f.png" width="40%"/>
+</p>
+
+
+## How can I do when confronted with the error of official use cases, saying that the target of LogWriter does not have the mode attribute?
+
+Please check the version of VisualDL you use (which visualdl). According to the error, it is most likely that you are using the VisualDL 1.3, which attributes to Python 2 you use. Python 2 will install the old version of VisualDL automatically.
+
+At present, VisualDL does not support Python 2 any more. And the instructions of existing official documents ae based on VisualDL 2.0, which also will not support Python 2. We suggest upgrading the Python's version to Python 3 and installing the latest version of VisualDL. In this way, the problem will not appear again.
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