1. This is the teacher whose course we are talking about.

2. This is the restaurant where we had a big party in. 

3. These reasons are the main ones which we are punished by. 

4. The astronaut who experienced some famous flight into space was born in Spain.

5. This is the best song in the album which I like very much.

.

Thay thế cho người: dùng who.

Thay thế cho sở hữu: whose

Thay thế cho vật: which

Thay thế cho nơi chốn: where 

1. Mình sửa đề qua 1 chút nhé. ( cause-> course; talking-> talking about)

This is the teacher whose course we are talking about. ( Mệnh đề quan hệ chỉ sự sở hữu: whose+ N)

2. This is the restaurant, in which/ where we had a big party. ( in which= where=> mệnh đề quan hệ thay thế cho danh từ chỉ nơi chốn)

3. These reasons are the main ones by which/ why we are punished. ( thay thế cho từ chỉ lý do, nguyên nhân.)

4. The astronaut who experienced some famous flight into space was born in Space. ( who thay thế cho danh từ chỉ người.)

5. This is the best song in the album which I like very much. ( which thay thế cho danh từ chỉ vật.)