A fruit can be hard.Logical formLearned from21 sentences. A literary-work can be hard.Logical formLearned from21 sentences. A force can be hard.Logical formLearned from21 sentences. A boom can be hard.Logical formLearned from21 sentences. A portion may pertain-to a hard drive.Logical formLearned from21 sentences. Facts can be hard.Logical formLearned from21 sentences. (Floor surfaces) can be hard.Logical formLearned from21 sentences. Material can be hard.Logical formLearned from21 sentences. A fit can be hard.Logical formLearned from21 sentences. A (golf course) can be hard.Logical formLearned from21 sentences. A trail can be hard.Logical formLearned from21 sentences. Hard hats can be blue.Logical formLearned from21 sentences. Hard drives may feature an ipod.Logical formLearned from21 sentences. Compounds can be hard.Logical formLearned from21 sentences. A team may make hard work of a campaign.Logical formLearned from21 sentences.