Instrumental (I)

I designates:

◊ the instrument, means,	(1)
◊ the agent (esp. in Ps constructions)	(2)
◊ together with, accompanied by (sociative) when used with 1) Adv/Prep saha, samam, sārdham & sākam and 2) Part sahita, saṅgata, yukta, anvita etc. and 3) cp sa- and saha-.	(3)
◊ separation and disjunction when used with Part such as rahita ‘wanting’, viyukta ‘disunited’, hīna ‘without’ etc (also constructed with Ab).	(4)
◊ equality, likeness, identity when used with sama, samāna, sadṛśa & tulya (also constructed with G).	(5)
◊ accompanying circumstances & qualitites	(6)
◊ declares the test to measure by	(7)
◊ the price or value, something is rated at in exchange	(8)
◊ the way by which one goes	(9)
◊ reason, cause, motive (also constructed with Ab).	(10)
◊ Causality must be put in I when: 1) the cause or motive occurs at the same time as the agent and 2) it is a feminine abstract expressing a quality (thus in scientific works, m °tvāt but f °tayā)	(11)
◊ points out points of comparision with √ and nouns, which denote superiority or inferiority, likeness or difference	(12)
◊ prohibition or an invitation to cease or to stop with alam, astu & kṛtam.	(13)
◊ in/over/through space	(14)
◊ (finished) within / during time	(15)

Examples:

Dātreṇa lunāti. (1)

‘He cuts withe the knife.’

Mayā tatkṛtam. (2)

‘It is done by me.’

Tvayā yuktaḥ. (3)

‘With you.’

Tvayā viyuktaḥ. (4)

‘Without you.’

Śakreṇa samaḥ. (5)

‘Equal to Śakra (Indra).’

Akleśena śarīrasya kurvīta dhanam sacayam. (6)

‘He must make money, but without giving toil to his body.’

Phalena etat jñāsyasi. (7)

‘You will know it by its fruit.’

Rūpaka-śatena vikrīyamāṇaḥ pustakaḥ. (8)

‘The book sold for a hundred rupees.’

Anayā bāla-pādapa-vīthyā sutanuḥ aciram gatā. (9)

‘The tender girl has passed a little before along this row of young trees.’

Vidyayā yaśaḥ. (10)

‘Fame by learning.’

Dhanena kuśalaḥ. (10)

‘Prosperous by wealth.’

Bhiyā palāyitaḥ. (11)

‘He fled from fear.’

Kim aham etābhyām śauryeṇa rupeṇa vidyābhyāsena kauśalena vā hīnaḥ. (12)

‘Am I inferior to both of them either in valour or in outer apperance or in study or in cleverness?’

Alam ākranditena. (13)

‘Stop your cries!’

Athavā, kṛtam saṃdehena. (13)

‘Well, no hesitation more.’

Adiṣṭena mārgena emi. (14)

‘I am going by the designated route.’

Saptāhena Avataṃsakasūtra-paṭhanam samāptam. (15)

‘Within a week the reading of the Avataṃsakasūtra was completed.’