1. Context Free Grammar S -> NP VP NP -> det (adj) N
NP -> Proper N
NP -> N
VP -> V, VP -> V PP
VP -> V NP
VP -> V NP PP, PP -> Prep NP
VP -> V NP NP
LING
NLP

2. Simple Context Free Grammar in BNF
S → NP VP
NP → Pronoun
| Noun
| Det Adj Noun
|NP PP
PP → Prep NP
V → Verb
| Aux Verb
VP → V
| V NP
| V NP NP
| V NP PP
| VP PP
LING
NLP

3. Simple Probabilistic CFG
S → NP VP
NP → Pronoun [0.10]
| Noun [0.20]
| Det Adj Noun [0.50]
|NP PP [0.20]
PP → Prep NP [1.00]
V → Verb [0.33]
| Aux Verb [0.67]
VP → V [0.10]
| V NP [0.40]
| V NP NP [0.10]
| V NP PP [0.20]
| VP PP [0.20]
LING
NLP

4. Simple Probabilistic Lexicalized CFG
S → NP VP
NP → Pronoun [0.10]
| Noun [0.20]
| Det Adj Noun [0.50]
|NP PP [0.20]
PP → Prep NP [1.00]
V → Verb [0.33]
| Aux Verb [0.67]
VP → V [0.87] {sleep, cry, laugh}
| V NP [0.03]
| V NP NP [0.00]
| V NP PP [0.00]
| VP PP [0.10]
LING
NLP

5. Simple Probabilistic Lexicalized CFG
VP → V [0.30]
| V NP [0.60] {break,split,crack..}
| V NP NP [0.00]
| V NP PP [0.00]
| VP PP [0.10]
VP → V [0.10] what about
| V NP [0.40] leave?
| V NP NP [0.10] leave1, leave2?
| V NP PP [0.20]
| VP PP [0.20]
LING
NLP