A part-time job can be challenging.Logical formLearned from3 sentences. Entry can be challenging.Logical formLearned from3 sentences. (Time constraints) can be challenging.Logical formLearned from3 sentences. A (research program) can be challenging.Logical formLearned from3 sentences. A (research agenda) can be challenging.Logical formLearned from3 sentences. (Conservation efforts) can be challenging.Logical formLearned from3 sentences. A movie can be challenging.Logical formLearned from3 sentences. A new field can be challenging.Logical formLearned from3 sentences. A (course material) can be challenging.Logical formLearned from3 sentences. A bar can be challenging.Logical formLearned from3 sentences. Poems can be challenging.Logical formLearned from3 sentences. (Technology issues) can be challenging.Logical formLearned from3 sentences. Collaborations can be challenging.Logical formLearned from3 sentences. (College courses) can be challenging.Logical formLearned from3 sentences. Certification can be challenging.Logical formLearned from3 sentences.