—Hurry up! Alice and Sue are waiting for you at the school gate.--- Oh! I thought they ____ without me.
My parents were not happy as they don't approve ____ out at night.
We haven't seen each other for 20 years, but I recognized him _____ I saw him.Which of the following is wrong ?
Life is the most important in the world so we should never compromise _____ safety standards.
Generally speaking, when _____ according to the directions, the medicine had no side effect.
________ it is expected that students come to college with the ability to solve most problems in their study by themselves , this is not always the case.