I can't understand why he ________ so selfish. He isn't usually like that.
A．was B．had been
C．is D．is being
—How long have you been going to work on foot?
—Since last month when I ________ from a heart attack.
A．recovered B．have recovered
C．was recovering D．would recover
Allen has decided that he will be an engineer by the time he ________ twenty.
A．had beenB．is going to be
C．will beD．is
．The sweater ________ easily; isn't it suitable for a person as lazy as you?
A．is washed B．was washed
C．washes D．has washed
—It seems that you know Dr. John very well.
—Of course, we ________ together for five years in the 1990s.
A．have worked B．had worked
C．are working D．worked
A recent survey shows the number of people who shop in stores ________， while far more are shopping online.
A.decrease B．decreases
C．is decreasingD．are decreasing
