僕は近道を通って森にもどり、小屋に錠をおろし、バスケットを開けた。

、、。

I took the shortcut back through the forest, locked the cabin, and opened the basket.

Literal

I [topic-は] shortcut [object-を] passing forest [to-に] returned, cabin [to-に] lock [object-を] lowered, basket [object-を] opened.

A sequence of three actions linked by the masu-stem conjunctive: もどり (返り), おろし, 開けた. This literary conjunctive form (verb stem without て) is characteristic of written narration. 近道を通って ('passing through the shortcut'). 錠をおろす ('to lock' — literally 'lower the lock').