Meaning: He looked fixedly at the birds flying around outside the window.
Choice of Words: Gazed means to look steadily and intently. Birds are flying animals with feathers and wings. Outside means not inside a building or a place.
Alternative Expressions
He looked at the birds outside the window.
Meaning: This sentence means the same as the first sentence, but it specifies that he was looking at the birds through a window.
Choice of Words:Looked means to direct one's eyes toward something. At means facing or directed toward something. Birds are creatures with wings that can fly. Outside means beyond the boundaries of something, in this case, outside the window.
He watched the birds flying in the sky.
Meaning: This sentence means that he was watching the birds as they flew in the sky.
Choice of Words:Watched means to look at something attentively. Birds are creatures with wings that can fly. Flying means moving through the air with wings. Sky means the space above the earth and below the clouds.