required: 美国〕必修的(大学课程), 必须的
This requires two sine-cosine resolvers .
necessary: 必需的,必不可少的
He lacks the necessary skills for the job.
required: 美国〕必修的(大学课程), 必须的
This requires two sine-cosine resolvers .
necessary: 必需的,必不可少的
He lacks the necessary skills for the job.