1.   Built to survive storms, the rig had a sturdy structure, but required new drilling equipment.

2.   But these institutions severely lacked the money for trained teachers and sturdy structures.

3.   Education and entertainment in one sturdy structure.

4.   He warned, however, that sturdy structures with windowless rooms provide the best shelter.

5.   It shows dense smoke billowing above sturdy structures.

6.   Even sturdy structures of cement and plaster were demolished.