The first page focuses on adverb clauses which are often called "time clauses" in English grammar books and follow specific patterns. Take a look at the chart below to study the various usage of different time expressions.
Punctuation When an adverb clause begins the sentence, use a comma to separate the two clauses. Example: As soon as he arrives, we will have some lunch. When the adverb clause finishes the sentence, there is no need for a comma. Example: He gave me a call when he arrived in town.
Adverb Clauses with Time