It seems like something is stuck in his trachea.

I am studying the philosophy of Guanzi.

This old radio uses a vacuum tube.

The male reproductive organs include the vas deferens.

She was told by the doctor that it is difficult to get pregnant due to a problem with her fallopian tubes.

The drainpipe is clogged and the water won't flow.

The exhaust pipe of my car has broken.

This old radio uses a cold-cathode tube.

This old radio uses a pentode.

Inside the ear, there are semicircular canals to maintain balance.