How to specify those intermediate CA certificates that form the signing chain for the server certificate for OpenSSl "verify" command? I have the certificate chain from the server saved in a file.

If you have the server certificate chain saved in a file, you can provide it to the OpenSSL "verify" command using the "-untrusted" option as shown below:

C:\Users\fyicenter>\local\openssl-win32\bin\openssl.exe

OpenSSL> verify -untrusted twitter_chain.pem twitter.pem
twitter.pem: C = US, O = DigiCert Inc, OU = www.digicert.com, 
   CN = DigiCert SHA2 Extended Validation Server CA
error 20 at 1 depth lookup:unable to get local issuer certificate
error in verify

The certification validation failed again with the same error: "unable to get local issuer certificate". But this time, it failed "at 1 depth lookup" instead of "at 0 depth lookup" as shown in the previous tutorial.

This tells us that the validation failed on locating the certificate of the issuer appeared on the intermediate CA certificate. To find out this issuer, we need to look at the content of the certificate chain file, "twitter_chain.pem".

C:\Users\fyicenter>type twitter_chain.pem

CONNECTED(0000017C)
---
Certificate chain
 0 s:/businessCategory=Private Organization/jurisdictionC=US/jurisdictionST=...
   i:/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert SHA2 Extended Validation Server CA
-----BEGIN CERTIFICATE-----
MIIHnTCCBoWgAwIBAgIQB3a13cqDpLnKWY9ddx+eRjANBgkqhkiG9w0BAQsFADB1
MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
d3cuZGlnaWNlcnQuY29tMTQwMgYDVQQDEytEaWdpQ2VydCBTSEEyIEV4dGVuZGVk
...
-----END CERTIFICATE-----
 1 s:/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert SHA2 Extended Validation Server CA
   i:/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert High Assurance EV Root CA
-----BEGIN CERTIFICATE-----
MIIEtjCCA56gAwIBAgIQDHmpRLCMEZUgkmFf4msdgzANBgkqhkiG9w0BAQsFADBs
MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
d3cuZGlnaWNlcnQuY29tMSswKQYDVQQDEyJEaWdpQ2VydCBIaWdoIEFzc3VyYW5j
,,,
-----END CERTIFICATE-----
---
Server certificate
...

Looking the content of the certificate chain, we know that the issuer at 1 depth is "DigiCert High Assurance EV Root CA", which is a root CA.

⇒ Download Root CA Certificate

⇐ OpenSSL "verify" - Verify or Validate Certificate

⇑ OpenSSL "verify" Command

⇑⇑ OpenSSL Tutorials