Criticism and self-criticism _____ necessary _____ it helps us to correct mistakes.

Ben looks strong. Has he ever been sick— He’s a superman! He ________ goes to the doctor.

________, but the idea of having to workmore than ten hours a day without weekends discouraged me.

Some of the European languages come from Latin，________ French，Italian and Spanish

The project turned out much more difficult than _____ [ ]