21.__________hard you try, it is difficult to lose weight without cutting down the amount you eat.
A Whatever B Whichever C However D Whenever
22. It was not until I came here _______I realized this place was famous for not only its beauty but also its weather.
A who B that C where D before
23.How I wish every family _______ a large house with a beautiful garden.
A has B had C will have D had had
