[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"external-kwt-1427":3},{"payload":4,"id":34,"user":35,"level":41,"course":42,"activity":43,"activity_slug":44,"title":45,"topic":46,"tone":47,"stats":48,"created":51,"score":52,"is_favorite":53,"public":54,"is_external":53},{"assessments":5},[6,11,16,21,26,30],{"tag":7,"keyword":8,"sentence":9,"challenge":10},"Superlatives","FAR","The most common mistake in formal emails is using language that is too informal.","Using language that is too informal is ............ mistake in formal emails.",{"tag":12,"keyword":13,"sentence":14,"challenge":15},"Cleft Sentences","DEALING","People most commonly misunderstand phrasal verbs when they try to translate them word for word.","What people ............ with phrasal verbs is translate them word for word.",{"tag":17,"keyword":18,"sentence":19,"challenge":20},"Passive Voice","FOUND","Among advanced learners, omission of articles is one of the most common grammar problems.","One of the grammar problems ............ learners is omission of articles.",{"tag":22,"keyword":23,"sentence":24,"challenge":25},"Relative Clauses","IMPROVE","Students most commonly improve their speaking by listening carefully to native speakers.","Listening carefully to native speakers is the way ............ speaking.",{"tag":17,"keyword":27,"sentence":28,"challenge":29},"to","Teachers often say that the most common reason for weak essays is poor planning.","Poor planning is often said ............ reason for weak essays.",{"tag":12,"keyword":31,"sentence":32,"challenge":33},"OFTEN","The most common complaint from C1 students is that they do not know which structure to use.","What C1 students ............ not knowing which structure to use.",1427,{"id":36,"username":37,"first_name":38,"last_name":39,"image":40},27272,"dalma-laura","Dalma","Laura","https://api.useofenglish.ai/static/img/users/default-profile-picture.jpg","C1","Reading","Keyword Transformation","keyword-transformation","Keyword Transformation #1427","Most common things","Standard",{"times_played":49,"num_favorites":50},2,0,"2026-08-22T18:52:51",null,false,true]