You must work hard to keep your brain active just

You must keep your promise.（英译中)

For many people today, reading is no longer relaxation. To keep up their work they must re

We must work hard to____ a good knowledge of English.A) inquireB) acquireC) requireD)

Since your work friends are just your friends in your workplace, you will never invite

To master a foreign language requires hard work, so you______study too hard.A．shouldB．must

For many people today reading is no longer relaxation. To keep up their work they must read letters