Breakdown of Il commence à comprendre la technique.
il
he
comprendre
to understand
à
at / to / in (general locations) / about (what one thinks about / reacts to)
commencer
to start
Questions & Answers about Il commence à comprendre la technique.
Why do we need à after commence?
In French, when a conjugated verb is followed by an infinitive (an unconjugated verb like comprendre), the first verb decides which preposition is needed to connect them. Commencer is a verb that requires à. You have to learn it as a set phrase: commencer à faire quelque chose (to start doing something).
Since the infinitive comprendre already means "to understand", isn't the à redundant?
It feels redundant to English speakers, but the à here belongs to commence, not to comprendre. French doesn't use à just to mean "to" before an infinitive. Instead, the first verb acts like a boss and dictates if a preposition is needed to attach the next verb.
How do I know whether to use à, de, or nothing before an infinitive?
Unfortunately, there is no overarching rule. You just have to memorize the preposition along with the verb when you learn new vocabulary. For example, it is always commencer à (to start to) and réussir à (to manage to), but décider de (to decide to), and vouloir (to want to) takes no preposition at all.
What if I wanted to say "He starts by understanding the technique"? Would I still use à?