Yours very truly,
Exercise 180
Write five sentences containing initial participial phrases.
Write five sentences containing initial adverbial clauses.
Exercise 181
The comma is used to separate the month from the year, the city from the county or state, the company from the place in which it is operated, or the like; as,
In December, 1912, I wrote to you from Seattle, Washington.
This use of the comma indicates that words have been omitted, the sentence above really meaning,
In December of the year 1912 I wrote to you from Seattle in the state of Washington.