+447.+ The third kind of clause which we may use in a complex sentence
is the adverb clause.
+An adverb clause is a clause which takes the place of an adverb.+ It
may modify a _verb_, an _adjective_, or an _adverb_. We studied adverb
clauses in lesson 21 and we found eight classes of adverb clauses,
expressing _time_, _place_, _cause_ or _reason_, _manner_, _comparison_,
_condition_, _purpose_ and _result_. For example:
1. +Adverb clause of time:+
No man is truly free _until all are free_.
2. +Adverb clause of place:+
We must live _where we can find work_.
3. +Adverb clause expressing cause or reason:+
We lost the strike _because the men were not class-conscious_.
4. +Adverb clause of manner:+
We must work _as if the result depended entirely upon us_.
5. +Adverb clause of comparison:+
The working class must become more class-conscious _than it is
today_.
6. +Adverb clause of condition:+
We will continue to be exploited _if we do not demand our rights_.
7. +Adverb clause expressing purpose:+
We must read the labor press _in order that we may know the truth
concerning conditions_.
8. +Adverb clause expressing result:+
The battle raged so furiously _that thousands were slain_.