切合 collocates very strongly with 实际 (reality), 需要 (needs), 主题 (topic), and 时代 (the times). The fixed phrase 切合实际 (qièhé shíjì) means 'realistic / down-to-earth' and is the form you'll meet most often.
mistakes
Don't confuse 切合 with 符合 (fúhé). 符合 is broader and usually means 'to conform to / be in line with' (符合规定 'comply with regulations'); 切合 is tighter — 'to fit precisely / be apt for' a situation, audience, or topic.
