Singular versus plural

There does not seem to be anywhere to ask a question on the test site: Vive le Printemps! posted 5/6/21. The sentence is: Je regards les bourgeons éclore dans les arbors fruitier - that is given as the correct answer. However, it seems that the correct answer would be "les bourgeons éclorent dans les arbors fruitiers

Je regards les bourgeons éclore dans les arbors fruitier. -- I watch the buds bloom in the fruit trees.

Èclore is the infinitive form and therefore doesn't match les bourgeons. It's the same in English: I watch him climb the tree. -- Climb isn't matched to him (or else it would be "climbs"). It doesn't function as a verb here, it describes a state. Technically it is an infinitive standing in for a gerund (=blossoming): I look at the buds blossoming in the fruit tree. -- Je regards les bourgeons éclorant dans les arbors fruitier.

Éclore (to bloom) is the infinitive. “I watch the buds to bloom” could be the translation of how they say this in French, for the English equivalent of “I watch the buds blooming”, or “I am watching the buds bloom”. If you just wanted to say the buds are blooming it would be “Les bourgeons éclosent” with éclore being conjugated in the present, but it’s the “Je regarde” that makes the difference. If there are 2 verbs in a row like this, the 2nd one is used in the infinitive. For example if you wanted to say “I see the children eating” you would say “Je vois les enfants manger”, not “Je vois les enfants mangent”. Or “I hear the man playing” would be “J’entends l’homme jouer”. 

Thanks to all who have responded. I appreciate you taking the time and your explanations. 

Wait--je regards? Isn't it regarde?

A typo, Stephanie.