留学签证，单位的准假信不是必需的，重点不是这么一份证明，而是这类证明的作用—表明你的留学动机和归国计划，消除你的移民倾向。

如果你的其他材料也可以很好的达到这一目的，就不需要强求准假信。至于辞职还是请假来英国学习，这取决于你的公司和你自己。

ABC INC.
66 88street XX City XXprovince
P R China 123456
TEL：( xxx)711111 FAX: (xxx)99999


June 11, 2006
TO WHOM IT MAY CONCERN,
This is to state that we approve of the sales manager Mrs./Mr XX(Annual income of 200,000 RMB), a full-time employee of the ABC INC., taking her vacation to attend her/his son’s convocation ceremony （or whatever）from 00/01/2006-01/02/2006 in Canada.
We will retain her/his position and continue to employ her when she/he returns to China.

Yours sincerely,


XXX General Manager