阅读下面短文, 掌握其大意, 然后从每题所给的A、B、C、D四个选项中选出最佳选项。 Last year in early summer, I was walking up the hill to my house when I saw two birds, each about 60 centimeters tall, standing on the path. They didn't seem to 1 me until I was right in front of them and then they at once moved 2 into the bushes.
I was quite excited by the idea of two birds making a nest in my front yard, although I didn't really expect it 3 wild birds don't usually nest so close.
A few weeks later, the birds4 again. I found them crouching(蜷缩) beside a tree off to the side of the path. As I moved nearer to them,I imagined that they would 5 like they did last time. But 6 they stuck out their heads and made a threatening(威胁的) croaking(呱呱叫) sound. It seemed to warn me not to go any7 .
I didn't know 8 they were croaking at me until a short time later I made an amazing discovery they had 9 small baby birds.
As I moved quietly towards the birds,10 not to make any sudden movements, they started their croaking again. They straightened their necks forward so 11 seemed longer and more threatening. The mother carefully crouched down over the two chicks, and 12 them well in her feathers.
I was watching them with 13 when I suddenly tripped and fell to the ground. The birds took this as a threat and the father raced towards me, spreading his14 to protect the mother and the chicks while making himself appear larger.
I was15 to have surprised them and left quickly. I was amazed by their fearless actions. Their parental natural ability kicked in and made them so brave. It is hard not to respect nature.