Professor Johnson is said _____ some significant advance in his research in the past years.

Bread and butter____liked by Westerners.

_____ if I had arrived yesterday without letting you know beforehand.

All of us would have enjoyed the party much more if there _____ quite such a crowd of people there.

If not _____with the respect he feels due to him, Jack gets very ill-tempered and grumbles all the time.