He is deeply involved in the study of Islamism.

He is deeply immersed in the study of Marxism.

He is deeply immersed in the study of Leninism.

He is a firm believer in capitalism.

He is an egoist, only thinking about his own benefits.

Natural language understanding is an important field of artificial intelligence.

His team achieved a comeback victory at the last moment.

His team pulled off a come-from-behind victory in the last five minutes.

He is bedridden and cannot go out.

He is an excellent doctor.