Wiktionary
make sure
vb. 1 (context idiomatic English) To verify; to recheck; to use extra care or caution. 2 (context obsolete English) To betroth.
WordNet
make sure
v. make a point of doing something; act purposefully and intentionally [syn: make a point]
Usage examples of "make sure".
These days his hand went to his heart for other reasons, to make sure that his pills were still in his breast pocket.