योगवासिष्ठः yogavāsiṣṭhaḥ - book-4, chapter-17, verse-12

पिशाचयक्षरक्षांसि सन्त्येवंरूपकाणि ह ।
संकल्पमात्रदेहानि सुखदुःखमयानि च ॥ १२ ॥

piśācayakṣarakṣāṃsi santyevaṃrūpakāṇi ha ,
saṃkalpamātradehāni sukhaduḥkhamayāni ca 12

12. piśācayrakṣarākṣāṃsi santi evamrūpakāṇi ha
saṅkalpamātradehāni sukhaduḥkhamayāni ca

12. piśācayrakṣarākṣāṃsi ha evamrūpakāṇi santi
ca saṅkalpamātradehāni sukhaduḥkhamayāni

12. Demons (piśāca), yakshas, and rakshasas verily exist in such forms; their bodies are solely mental creations (saṅkalpa), and they are characterized by pleasure and pain.

Words meanings summery:

• पिशाचय्रक्षराक्षांसि (piśācayrakṣarākṣāṁsi) - demons, yakshas, and rakshasas

• सन्ति (santi) - are, exist

• एवम्रूपकाणि (evamrūpakāṇi) - having such forms, of such a nature

• ह (ha) - indeed, verily, surely

• सङ्कल्पमात्रदेहानि (saṅkalpamātradehāni) - whose bodies are merely mental constructions (saṅkalpa)

• सुखदुःखमयानि (sukhaduḥkhamayāni) - consisting of pleasure and pain, full of joy and sorrow

• च (ca) - and

Words meanings and morphology

पिशाचय्रक्षराक्षांसि (piśācayrakṣarākṣāṁsi) - demons, yakshas, and rakshasas

(noun)

Nominative, neuter, plural of piśācayrakṣarākṣas

piśācayrakṣarākṣas - demons, yakshas, and rakshasas (collectively)

Compound type : dvandva (piśāca+yakṣa+rakṣas)

• piśāca – demon, goblin, vampire
  noun (masculine)
• yakṣa – yaksha (a class of benevolent nature-spirits)
  noun (masculine)
• rakṣas – rakshasa, demon, evil spirit
  noun (neuter)

सन्ति (santi) - are, exist

(verb)

3rd person , plural, active, present (lat) of as

Present active indicative, 3rd person plural

Root: as (class 2)

एवम्रूपकाणि (evamrūpakāṇi) - having such forms, of such a nature

(adjective)

Nominative, neuter, plural of evamrūpaka

evamrūpaka - of such a form or nature

Compound type : bahuvrīhi (evam+rūpaka)

• evam – thus, so, in this way
  indeclinable
• rūpaka – form, image, semblance, nature
  noun (neuter)

ह (ha) - indeed, verily, surely

(indeclinable)

सङ्कल्पमात्रदेहानि (saṅkalpamātradehāni) - whose bodies are merely mental constructions (saṅkalpa)

(adjective)

Nominative, neuter, plural of saṅkalpamātradeha

saṅkalpamātradeha - having a body that is merely a mental creation/resolve

Compound type : bahuvrīhi (saṅkalpa+mātra+deha)

• saṅkalpa – mental conception, intention, resolve, will
  noun (masculine)
  Prefix: sam
  Root: kḷp (class 1)
• mātra – mere, only, simply (as suffix)
  indeclinable
• deha – body, form
  noun (masculine)

सुखदुःखमयानि (sukhaduḥkhamayāni) - consisting of pleasure and pain, full of joy and sorrow

(adjective)

Nominative, neuter, plural of sukhaduḥkhamaya

sukhaduḥkhamaya - consisting of pleasure and pain, full of happiness and sorrow

Compound type : tatpuruṣa (sukha+duḥkha+maya)

• sukha – pleasure, happiness, joy
  noun (neuter)
• duḥkha – pain, suffering, sorrow, misery
  noun (neuter)
• maya – consisting of, made of, full of (as suffix)
  adjective (neuter)
  Suffix indicating material or abundance.

च (ca) - and

(indeclinable)