情态动词是系动词吗

情态动词不是系动词。系动词可以单独作谓语，如：She looks very beautiful.她看上去很美丽。情态动词除need有时可作实意动词而单独做谓语外，必须同实意动词一起作谓语。如：You must study hard.你一定要努力学习。

Would you mind opening the Windows.你介意打开窗户吗��