On two occasions she had peeked at him through a crack in the wall.
有两次她曾透过墙上的一个裂缝偷窥了他。
《柯林斯英汉双解大词典》
2
One day to the joyful surprise of the pair there appeared in the party wall a tiny crackthrough which they could murmur endearments and even exchange sweet kisses.
Through adding low viscidity HPMC, workable performance of the dry-mixed mortar can be greatly improved, and this dry-mixed mortar can well solve the crack problem of wall.