他们在沙漠中挖掘时意外惊动了一只巨大的地底怪物。

They accidentally disturbed a huge ___graboid while digging in the desert.

孩子们在后院玩耍时假装有只沙虫从地下钻出来。

The kids pretended a ___graboid was burrowing up from the ground while playing in the backyard.