A. is B. are C. was D. were
A. know B. known C. have known D. is known
A. will be B. had been C. have been D. has been
A. were reviewing B. was reviewing C. has been reviewing D. have been reviewing
A. who have been invited B. who has been invited C. whom they have invited him D. whom has been invited
A. grazes B. is grazing C. was grazing D. were grazing
A. have realized B. has realized C. have been realized D. has been realized
微信支付 
支付宝支付