I am feeling rather off today.

还可以说off colour=(unwell/ill)感到不舒服

rather=quite=very

=I am feeling very unwell today.

off用在系动词feel后作表语，
rather副词，修饰off

rather是非常
off是不舒服

off
KK: []
DJ: []
ad.
1. (离)开,(走)开,(隔)开
They went off together and left me sitting there.
他们一同离开了,留下我独自坐在那里。
2. (时间、空间上)离,距
The town is five miles off.
小城离这儿五英里远。
3. 切断,关掉,停止;取消;不在工作,休息
He turned off the light before going out.
他出门前把灯关掉。
4. 完,光,直到最后
I've paid off my debts.
我已把债款还清了。
5. (食品)变坏,变质;不再供应
The milk has gone off.
这牛奶已变质。
6. 不如通常水平
7. (消)除,(去)除
prep.
1. 离开...,隔着...;在(离岸边不远的)海面
He lifted a cup off the table.
他从桌上拿起一只杯子。
2. 从...脱落,从...掉下
3. 偏离...;失去...
You're going off the subject.
你们离题了。
4. 通向...;从...分岔
The dining room is off the living room.
餐室通向起居室。
5. 戒掉...;停服...
He is off smoking.
他戒烟了。
6. 以...为依靠,以...为食<