单项选择题
二极管截止的条件是阳极电位高于阴极电位。
未知题型二极管截止的条件是阳极电位高于阴极电位。
They spent one year abroad simply （） _____________their...
未知题型They spent one year abroad simply （） _____________their mind.
Compare each pair of words and complete the following s...
未知题型Compare each pair of words and complete the following sentences with the right one. Change
