break into=enter by force，pv，vt闯入

The police broke into the building occupied by criminals.

blitz= an intensive or sudden military attack.闪电战，可数

Hamas launched a heavy blitz against Israel last Saturday.

proclaim=announce officially or publicly，vt，宣布，注意和claim的区别

The establishment of the state of Israel was proclaimed by its founder in 1948.

swear有“使…宣誓”的意思，vt

My students sworn to get a 7 IELTS overall band score are studying really hard.

maintain 除了有保持的意思，还有坚称的意思，相当于assert，vt

He maintains it’s not his fault that caused this accident.

crossfire= gunfire（炮火，不可数） from two or more directions passing through the same area.交叉火力，不可数

People in Gaza are now trapped in the crossfire.

catch sb off guard打某人个措手不及

Joe is caught off guard by one of his colleagues who’s falsely reported his wrongdoings to their boss.

desecration=the action of desecrating（desecrate，vt，treat a sacred place or thing with violent disrespect）sth，亵渎神圣，不可数。

Hamas claimed the assault on Israel was partly a response to the latter’s desecration of a holy site.

Judaism犹太教，其中a发ei的音，i也要发音；Islam，伊斯兰教，注意a发a的因，不发ae的音。

compound，complex，premises都是建筑群，区别是premises一定要用附属，前两者可以用单数

groundwork=preliminary or basic work，基础工作，不可数（lay the groundwork for…，为…打基础）

My students are learning English wholeheartedly to lay the groundwork for their studies abroad.

Hostility居然可以作可数名词，复数为hostilities，敌意

That blitz marked a steep escalation of hostilities between those two countries.

Infiltration= the action of entering or gaining access to an organization or place surreptitiously(偷偷地）, especially in order to acquire secret information or cause damage.潜入（尤指做坏事），可数

A large-scale infiltration into this country began under the cover of missiles.

mediation= intervention in a dispute in order to resolve it，调解，不可数

No one is believed to be able to bring mediation between these two opponents.