Page 49 - Practical English Usage 3ed - Michael Swan, Oxford

adverb position (2): front position 22
Adverbs of manner (how), place (where) and time (when) most often go in end position.
She brushed her hair slowly. The children are playing upstairs.
I phoned Alex this morning.
Time adverbs can also go in front position.
Tomorrow I've got a meeting in Cardiff.
For more details about the position of these and other kinds of adverb, see the next four sections.
22 adverb position (2): front position
Adverbs that usually go in front position: connecting adverbs (e.g. then, next); comment adverbs (e.g. fortunately, surprisingly); maybe, perhaps.
Adverbs that can go in front position: some adverbs of indefinite frequency (e.g. sometimes); adverbs of place; adverbs of time.
1 connecting adverbs: then, next, ...
These adverbs join a clause to what came before. Examples: then, next, besides, anyway, suddenly, however.
I worked until five o'e/ock. Then I went home.
Next, I want to say something abollt the fUture.
Suddenly the door opened.
Some of us want a new system However, not everybody agrees.
Other positions are possible.
I went home then. Not everybody, however, agrees.
2 comment adverbs: fortunately, surprisingly, ...
Adverbs which give the speaker's opinion of an action most often go in front position.
Fortunately, she has decided to help us. Stupidly, I forgot my keys. Mid-position is also possible.
3 indefinite frequency: usually, normally, ...
USllO.lly, normally, often, frequently, sometimes and occasionally can go in front position (but they are more common in mid-position - see 24.)
Sometimes I think I'd like to live somewhere else.
Uswzlly I get up early.
Always, ever, rarely, seldom and never cannot normally go in front position.
I always/never get up early. (NOT AIW6}'91IVeuer .. get ttp ettrly.) However, always and never can begin imperative clauses.
Always look in the mirror before starting to drive. Never ask her about her marriage.
4 certainty: maybe, perhaps
Maybe and perhaps usually come at the beginning of a clause. Maybe I'm right and maybe I'm wrong.
Perhaps her train is late.
Other adverbs of certainty (e.g. probably, definitely, certainly) usually go in mid-position.
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