Connectives
提示The signposts that tell a reader which way the argument is about to turn.
为什么They do real work: 'however' promises a contrast and 'therefore' promises a consequence, so the wrong one misleads the reader about your argument. 'Connective' is a classroom umbrella term, not a grammatical one — the DfE glossary has no entry for it. It calls 'however', 'therefore' and 'meanwhile' adverbs, calls 'and' and 'but' conjunctions, and groups both under cohesive devices. The split matters when you punctuate: 'but' can join two clauses after a comma, 'however' cannot — 'He was tired, however he kept going' is a comma splice.