I had only just put the phone down when the boss rang back.

48/50

I put the phone down when the boss rang back.

Hardly had I put the phone down when the boss rang back.

No sooner had I put the phone down when the boss rang back.

Scarcely had I put the phone down than the boss rang back.

Giải thích

Đáp án B

"Tôi chỉ mới đặt điện thoại xuống thì sếp gọi lại." _ Ngay khi tôi đặt điện thoại xuống thì sếp gọi.

Cấu trúc: Hardly/ Scarcely + had + S + pp ... + when + a clause ~ No sooner + had + S + pp ... + than + a clause (ngay khi... thì)