6、______atthistimeyesterday?A.did;doB.is;doingC.were;doingD.are;doing()20.---What’swrong?---Ifoughtwithmyfriendthismorning.---___________.A.That’snothing!B.Great!C.Let’splaysoccerD.Youshouldsaysorrytohim.()21.Look!Thereare____ youngtreesonthehill.A.hundred B