The machine has been used many years_____ it doesn’t work well occasionally.

A. That’s because             B. It’s no wonder that   

C. There’s no doubt if         D. It’s unlikely that

The machine has been used many years. _____it doesn’t work well occasionally.

A. That’s because　 B. It’s no wonder that

C. There’s no doubt if　 D. It’s unlikely that

The machine has been used many years_____ it doesn’t work well occasionally.

1. A.
   That’s because
2. B.
   It’s no wonder that
3. C.
   There’s no doubt if
4. D.
   It’s unlikely that

The machine has been used many years. It's no wonder that it doesn't work well ________．

A．regularly  B．constantly

C．occasionally  D．frequently