问题

In communication, a smile is usually _ strong sign of a friendly and _ open attitude.

A:the /
B:a an
C:a /
D:the an

正确答案是：

同类题型

___ you interrupt now Can’t you see I’m on the phone—Sorry Sir, but it’s urgent.

Listen! There is a knock on the door.Who _____ it be?—It must be Jack.Just now I sent for him. [ ]

Who______ the book ______by—–A famous English writer.

Do you know __________—I’m not sure. Maybe an English teacher

下列加点字的读音全都正确的一项是( )