I am thankful to you for suggesting a way out.
I tried the method mentioned by you. While most of the sentences were automatically translated, a few of them were left in English only. What should I do in this case?
Dear P. Chopra,
there is no such thing as a workbench file. You (and your client) probably mean a word document. Just use the "translate" function of the workbench on your source word document, with the TM you made while translating in TE.
There might be some tweaking necessary, but generally, that's it.