A patch can be challenging.Logical formLearned from4 sentences. A (crucible exercise) can be challenging.Logical formLearned from4 sentences. (Skating stunts) can be challenging.Logical formLearned from4 sentences. Hiking can be challenging.Logical formLearned from4 sentences. A city can be challenging.Logical formLearned from4 sentences. A plan can be challenging.Logical formLearned from4 sentences. The atmosphere can be challenging.Logical formLearned from4 sentences. Rounds can be challenging.Logical formLearned from4 sentences. An offer can be challenging.Logical formLearned from4 sentences. (Driving conditions) can be challenging.Logical formLearned from4 sentences. Lyrics can be challenging.Logical formLearned from4 sentences. Friends can be challenging.Logical formLearned from4 sentences. Downs can be challenging.Logical formLearned from4 sentences. (Nonconference games) can be challenging.Logical formLearned from4 sentences. A testing may prove challenging.Logical formLearned from4 sentences.