We must guard against our mistakes.

We must help him. (Negative) = We can not but help him.

We not only gave him food but also shelter.

We reached the station after the train had come.

We refused his invitation.

We shall discuss about the matter. = We shall discuss the matter.

We should abide by the rules.

We should abide by the law.

We should love our country. (Imperative) = Let us love our country.

We should not hanker after money.

We should respect our teacher, shouldn't we?

We trust to Allah.

We were not only poor but also unwilling to work hard.

We're well-off for public transport here.

Weal and woe =  Weal and woe comes by turns